1. Field
Aspects of the present invention relate to a secondary battery.
2. Description of the Related Art
In general, unlike primary batteries, which are not chargeable, rechargeable batteries are chargeable and dischargeable. Low-capacity secondary batteries, each comprised of a single unit cell, are widely used in small portable electronic devices, such as mobile phones, camcorders, or the like. On the other hand, large-capacity secondary batteries, each comprised of multiple battery cells, may be used as motor driving power sources, such as a hybrid electric vehicle (HEV) or the like.
A secondary battery may be manufactured in various shapes, e.g., a cylindrical can type, a rectangular or prismatic can type, or the like. The secondary battery may be configured by accommodating an electrode assembly including positive and negative electrode plates and a separator located therebetween within a case together with an electrolyte, and coupling a cap assembly having electrode terminals to the case.
If an internal pressure of a secondary battery rises due to generation of excessive heat or decomposition of an electrolyte, a fire or explosion of the secondary battery may occur. Accordingly, there is a need for a secondary battery having improved safety.